Condensate return system



Aug. 20, 1935.

L. o. GOFF 2,0 CONDENSATE RETURN SYSTEM I Filed July -9, 1934 2 Sheets-Sheet 1 L ear/4rd D. 6aff Aug. 20, '1935. L. D. GQEF 2,011,626

CONDENSATE RETURN SYSTEM Filed July 9, 1934 2 Sheets-$heet 2 Patented Aug.120,. 1 93 5 UNIT-E sr rE counnn'sarn RETURN SYSTEM- Leonard n. Golf, Three Rivers, Mich. Application July 9, 1934, serial No. 7134,255v

The invention relates to a return-system and method andv particularly to an improved system and method for returning condensate tobollers bymeans of a return trap, theuse of which is not 5 limited by lack of head room above boilers or lack of means for elevating the condensate to a return trap located over the boiler, and a system that; inaybe used on high pressure boilers'as well as 10 Heretofore return traps have been oifered as a moreeconomical and eflicient method for returning condensate to boilers, particularly high pressure, but their use has been limited to those places where the trap could be located above the boiler so that the condensate might drain by gravity into the boiler, the speed of draining depending on the elevation of the trap above the water line in the boiler and the resistance offered by necessary elbows, fittings and check valves. With the old systems it has been necessary to carry enough." pressure on a line to elevate the condensate to the trap above the boiler either directly, or by means of a lift trap which was supplied with the necessary pressure direct fromjhe boiler. Other-' wise it has been necessary to use power operated pumps which are expensive and in many cases inefioient. i r

An object ofthis' invention is to overcome the above difliculties by equalizing the pressure in the 30 trap with that in the boiler and pumping the condensate from the trap into the boiler against a head independent of the prms'ure in the boiler.

Another objectfiof this invention is to equalizeth,pressure in the trap with that in the boiler when the trap is below' the water levelin the boiler and topump the condensate from the trap into the boiler against a head equivalent only to the height through; which the condensate must be lifted, thus reducing the power required for pump- 4 ing to a minimum.

' Still another object of this invention is to provide a system for pumping fluid from a. low pressure container to a high pressure container wherein the pressure in the low pressure container is and thepump works only againstia. head equiv-' alent to the height to which the fiuid'must be lifted. I .7 I

Another object of this invention is to provide a return system for transferring condensate from a return trap to a boiler wherein, upon thecon-V densate .in the trap reaching a predetermined "level, the pressure imthetrap is equalized with that in the boiler and the pump becomes opera- "tive to transfer the condensate from the trap-to equalized with that in thehigh pressure container s Claims. (01.103-26) the boiler against a head equivalent only to the height to which the condensate must be lifted. h These and other objectswill be apparent from the following specification when taken with-the accompanying drawings in which,

' Fig. 1 is a general plan of the apparatus and connections included in the system, and n Fig. 2 is a vertical section through the trap disclosing the operative mechanism therein and the details of the mercury switch.

Referring particularly to Fig. 1, the reference character 'I- designates a return trap. A centrifugal pump 2 receives condensate from the bottom of the trap I and 'is connected to pump the condensate through a check valve 3, the gate 15 valve i and the pipe 5 to the bottom'of the boiler 6; The boiler G is provided with a dome! and has communicating therewith the pipe 8 for conducting pressure steam to the trap I. The trap I is not a part of .this invention'and is more fully 20 described both as to operation and as to structure in my, copending application Ser. No. 732,822, filed I Julie 28, 1934. V Condensate is admitted to the trap I through the pipe 9 having therein the gate valve I0 and the 25 check valve II. In order to vent the air in the trap I while condensate is flowing into it the vent pipe I2 is provided to provide a communication between the .trap I and-the atmosphere.

The source of supply of the condensate passing through the pipe- 9 depends upon-the complete system in which this invention is used. For instance, it might be received directly from a plurality of individual steam traps. Another source might be as shown in dotted lines in Fig. 1 where- .in the condensate is' collected in the tank I3 through the pipe IQ and is fed bygravity therefrom through the pipe I5 to thepipe 9.

The pump 2 is-preferably electrically driven and is started and stopped by a suitable switch 4 such as a mercury switch generally indicated by the housing I6 in Fig. 1; A conducton I1 com' pletes the circuit between the mercury switch and the pump 2.

Referring particularly .to-Fig. 2 disclosing a vertical section of the trap I, the trap I is provided with a "casing 20'having secured thereto a cover plate 2 j. Disposed on the top of the cover plate 2| is.a pressure steam inlet housing 22 communicating through the pressure steam inlet valve 23 with the interior of the: casing 20. Likewise secured to the top of the cover plate 2| is a vent housing 2 communicating through the vent valve 25 with the interior; of, the casing 20. Within the casing 20 is disposed a float 26 for 25, slidably secured we lost motion connection to the-spindle 21. The adjustable collar 28 and the U-shaped 'strip 23' both secured to the spindle .21 define the limits of the lost motion connection of the float 26 on the spindle 21. The valves 23 and 25. are operated directly by a toggle having arms 30 and 3! supported at their interior ends by the U-shapedstrip 29 and at their exterior ends by the inwardly urged spring strips 32 and 33, respectively. The c'onnectionsat-eachend" of the toggle levers 30 and-3| are pivotal. Depending fromthe valves 23 and 25 are elongated stems 34 and 35 respectively having L-shaped connectors 36 and 31 each secured by a lost mobetween the collars 39 and. is the arm 4| of the mercury switch 42 mounted in the housing IS. The housing I6 is supported from the cover plate 2| by the bracket 43. The mercury switch 42 comprises a bulb 44 having a plug of glass or of some other suitable insulating material sealing one end. Molded in the plug 45 are two elec trodes 46 and 41 extending into the interior oi the bulb 44. Mercury 48 is disposed within the bulb 44 for-bridging the gap between the electrodes 46 and 41. The switch 42 is pivotally mounted on the pin 49 being supported thereon by the arm 50 connected to the arm 4|.

The operation of the-mercury switch is such that when the float 26 is at its lowermost position the switch is tilted to the left and the mercury 48 is away from the electrodes 46 and 41. Fur ther tilting to the left isprevented by the arm 4| resting angularly against the spindle 21. When the condensate rises to such a level in the casing 20 that the valve 23 opens and the valve 25 closes I the collar-39 engages with the arm 4| to rock the mercury switch to the right whereby the mercury 48 bridges the gap between the electrodes 46 and 41 and closes the pump circuit in which they are included. Further tilting to the right of the switch 42 is prevented by the arm 4| angularly resting against the spindle 21. A flexible con-v nection 5| connects the electrodes 46 and 41 with the conductor I1 leading to the centrifugal pump 2.

The operation is as follows: Assuming that the trap is ez'nptyand that the condensate is flowing through the'pipe 9 into the trap, the position of the pressure. steam valve 23, the vent valve 25, the float 26 and the mercury switch "will be as shown in Fig. 2. Highpressure steam is excluded by the valve 23 and the interior of the casing 20 of the trap I is open to the atmosphere through the Upon the level of the condensate within the casing 20 ris ing to such a height that the float 23 strikes the -collar28, the-spindle 21 is lifted carrying with it the inner end of the toggle levers 30 and 3| and the arm 4| of the mercury switch 42. When the toggle levers 30 and 3| are raised to a position just past that of horizontal alignment thepinwardly urged springs 32 and 33 snap the toggle levers rapidly upwardly opening the steam valve 23 and closing the ventvalve 25.- -At the same time the collar 39 on the spindle 21 lifts the'arm 4| upwardly a suflicient distance tooverbalance the switch 42 to tilt it to the right whereat the merr 2,011,62d operating the switch l8 and the'valves 23 and cury 48 :bridges the gap between the electrodes 46 and 41 to close the pump circuit to start the I pump. a 1

The opening of the valve. admits pressure steam into the casing 2|! and the closing otthe valve 25 prevents its escape. Pressure steam is also prevented from escaping through the condensate inlet pipe 9 by the check valve The pressure in the trap is thus equalized with that in the boiler 6. Condensate in the casing 23 of the trap is constantly in communication through the opening 52 in the bottom of the casing 26 with the pump 2; The condensate is prevented from passing out ofthepump 2 by the check valve 3 maintained closed by the boiler pressure passing through the pipe 5 and the gate float 26 falls and brakes the U-shaped strip, 29

whereupon the position of the toggle 30 and 3| is,

reversed to close the steam valve 23 and open the vent valve 25. At the-same time the collar 40 on the downwardly moving spindle engages the arm 4| or the mercury switch'42. The mercury switch 42 is then tilted to the left whereby the mercury 48' in the bulb 42 flows, due to the action .of gravity, from across the electrodes 46 and 41 to open the pump circuit. The pressure in the casing 20 of the trap is vented to the atmosphere by the opening of the valve 25 and condensate 'may again enter throughthe pipe 9. f

It will become apparent that I. have provided a return trap and pump combination in which the boiler pressure is equalized upon the condensate being pumped or at least. utilized to some extent to facilitate the return of thecondensate to the boiler resulting in the size of the pump and operating power required being reduced to a minimum. Also, I have provided a return trap and pump combination-in which the discharge of the trap and operation of the pump is synchronized and the same source of pressure isutilized to facilitate d the discharge of the trap and pumping of the condensate against boiler pressure. 4 Theuse of any type of pump in which the equalized pressure upon the condensate is made available to th pumping operation, is contemplated.

While the foregoing specification has described a specific trap as beinga part of thesystem comprising this invention it is contemplated that any suitable trap may be used including those known as tilt traps" and floated weight traps. If desired the condensate inlet pipe 9 may be conneoted to the inlet 52 at the bottom of the trap instead of to the side near the top as shown. Further this invention is not limited to a centrifugal pump and either manually or power -operated pumps may be used. Further this invention is not inbuoyancy of water, may besubstitutcd. While it is also preferred that the pressure in the trap be equalized with that in the boiler, it is intended that constructions wherein the pressure differential between the boiler and the tr'ap is reduced be included within the scope of the invention. I

scope of the following claims.

I claim:

1. A return system for association with a steam boiler comprising means for receivingcondensate, means for equalizing the pressure in said receiving means with the pressure in the boiler when the condensate in said receiving means has risen therein to a predetermined level, and means while operative substantially continuously subject 'to the pressure in said receiving means for positively transferring the condensate from said receiving means to said boiler while said pressures .are equalized, whereby the head against which said transferring means operates is independent of the pressure in the boiler,

2. A returnsystem for association with a steam boiler comprising means for receiving condensate, conduit means connecting the boiler and said receiving means, pumping means insaid conduit for positively transferring the condensate'from said receiving means to said boiler, means for equalizing the-presiure in said receiving means with the pressure in the boiler, and means initiat- "ing the operation of said pump concurrently, with the equalizing of the pressure in the boiler and saidreceiving means, whereby the head against which said pumping means operates is independent of the pressure in the'boiler.

3. A return system for association with a steam boiler comprising means forreceiving condensate .disposed below the level of the boiler; means for equalizing the pressure in said receiving means with the pressure in said boiler when the condensate in said receiving means has risen therein to a predetermined level, and means while operative substantially continuously subject to the pressure in said receiving means disposed between said receiving means and the boiler for transferring the condensate from said receiving means to said boiler while said pressures are equalized, whereby the head against which said transferring' means operates is independent of the pressure in the boiler. 4

4. A return system for associationwith a steam boiler comprising means for receiving condensate disposed below the level of the boiler, means dependent on the level of the condensate in said receiving means for equalizing the pressure in said receiving means with that in the boiler, and means while operative substantially continuously subject to the pressure in said receiving means disposed betweensaid receiving means and the I boiler operative to transfer the condensate from said receiving means to said boiler -while said pressures are equalized, the operation of said means being controlled by the level of the condensate in said receiving means, ,whereby the head against which said transferring means operates is independent of the pressure in the boiler.

5. A return system for association with a steam boiler comprising means for receiving condensate,

disposed below the level of the boiler, mechanism associated with said receiving means operative, upon the level of the condensate in said receiving means reaching a predetermined level, to equalize the pressure in said receiving means with the pressure in the boiler, and a pump while operative substantially continuously subject to the pressure in said receiving means disposedbetween said reboiler, and means while operative substantially continuously subject to the pressure in said receiving means disposed between said receiving means and the boiler operative positivelyto transfer the condensate from said receiving means to operation of said means being controlled by the level of the condensate in said receiving means, whereby the head against which the transferring means operates is independent of the pressure in the boiler. I I

7. A return system for association with a steam boiler comprising means for receiving a condensate mechanism associated with said receiving means operative, when the level of the condensate in said receiving means reaches a predetermined level, to equalize the pressure in said receiving means with the pressure in said boiler, and pumping means while operative substantial y continuously subjectt'o the pressure in said receiving means disposed between said receiving means and. the boiler for transferring the condensate from. said receiving means to said boiler while said pressures are equalized, whereby the head against which the pumping means operates is independent of the pressure in the boiler. 4

8. A return system for association with a steam boiler comprising a return trap for receiving a condensate disposed below the level of said boiler, mechanism associated with 'said return trap operative, upon the level of the condensate in said return trap reaching a predetermined level, to equalize the pressure in said return trap with that in the boiler, and a pump while operative substantial ycontinuously subject to the pressure in said trap for transferring the condensate in said trap to saidboiler while said pressures are equalized, whereby the head against which the pump operates is independent of the pressure in the boiler.

9. A return system for association with a steam boiler comprising a return trap for receiving condensate, a conduit connecting the boiler with said trap, a pump in said conduit while operative substantially continuously subject to the pressure in saidtrap for pumping condensate from said trap to said boiler and means both for equalizing the pressure in said boiler and'in said trap'and for starting said pump upon therising of the condensate in said trap to a predetermined level,-

- whereby the head against which the pump opcomprising means to equalize the pressure in said .said boiler while said pressures are equalized, the

low pressure container with that in the high pressure container, and means while operative substantially continuously subject to the pressure in said low pressure container for positively transferring the fluid from said low pressure container to said high pressure container while said pressures are equalized whereby the head against which said transferring means operates is independent ofthe pressure in the high pressure com I talner.

11. A system for discharging a fluid from a low pressure container to a high pressure container comprising-means for reducing the diflerential pressure between-the low pressure container and the high pressure container and means while operative substantially continuously subject to the pressure in said low pressure container for positively transferring the fluid from said low pressure container to said high pressure container whereby the head against which said transierring means operates is less than the pressure in the high pressure container. I

12. A system for discharging a fluid from a low pressure container into a high pressure container comprising mechanism associated with said low pressure container to equmize the pressure there.- in with the pressure in the h gh pressure container, and means while operative substantial'y continuously subject to the pressure in said low pres-. sure container for transferring the fluid from said low pressure container to the high pressure container while said pressures are equalized, said means, eing-controlled by theccndition existing within the low pressure container whereby the head againstwhich said transferring means operates is independent of the pressure in the high pressure container.

- 13. A system for discharging a fluid from a low pressure container into ahigh pressure container comprising a pump while operative sub tantially continuously subject to the pressure in aid low pressure container for transferring fluid from the low p'ressurecon'tainer to the high pressure container, and means operative to equalize the pressure in the low pressure container with that of the high pressure container and to start said pump, upon the raising'of the condensate in said container to a predetermined level, whereby the head against which said pump operates is independent of the pressure in the high pressure container.

14. A system for discharging a fluid from a low' pressure container into a high pressure container comprising means for connecting the high pressure container with the low pressure container for equalizing the pressures therein and means while operative substantially continuously subject to the pressure in said low pressure container for positively transferring fluid from said low pressurecontainer to said high pressure container while said pressures are equalized whereby the head against which said transferring means operates is independent of the pressure in the boiler.

15. A- return system for association with a steam boiler comprising means for receiving a condensate, mechanismlassociated with said retainer which comprises equalizing the pressure in the low-pressure container with that in the high 7 pressure container and positively transferring the fluid through a closed connection from the low pressure container to the high pressure container while said transferring means is substantially continuously subject to the pressure in the low pressure container, vwhereby said fluid is' transferredto the high pressure container against a head independent of the pressurein the high pressure container.

17. The method of returning condensate to a boiler which comprises collecting the condensate in a trap, and equalizing the pressure in the trap with that in the boiler while pumping the condensate from the trap to the boiler against a head independent of, the boiler pressure.-

18. The method .of transferring a fluid from a low pressure container to a. high pressure container which comprises collecting the fluid at atmospheric pressure in a collector, equalizing the pressure in the collector with that in the boiler and simultaneously pumping it into the high pressure container against a head independent of the boiler pressure.

19. The method of transferring a fluid from a low pressure container to a high pressure con tainer which comprises reducing the differential pressure between the low pressure container and the high pressure container, and positively transfering the fluid through a closed connection from the low pressure container to the high pressure container against a head/less than the pressure in the high pressure container.

monARD D. (307::"11".-

I CERTIFICATE OF CORRECTION. Patent No. 2,011., 626. i J August 20, 1935.

. LEONARD in. corr.

It is hereby certified that error appears in the printed specifioation of the, above numbered patent requiring correction as follows; Page 2, second colu xin, line 27, for

f'brakes" read strikes; and that the saidLetters Patent should be read with this correction-therein that thesame n ay conforrn'to' the record of the case in the Patent Office.

Signed and sealed this 24th day of September, A. D. 1935. Y

Leslie Frazer I (Seal) Acting Commissioner of Patents. 

